From something as small and complex as a chromosome to something as seemingly simple as the weather, sex determination systems vary significantly across the animal kingdom. Biologist and teacher Aaron Reedy shows us the amazing differences between sp...ecies when it comes to determination of gender. (05:45)[more]

What do a man, a mushroom, and an elephant have in common? A very long and simple double helix molecule makes us more similar and much more different than any other living thing. But, how does a simple molecule determine the form and function of so ...many different living things? (04:26)[more]

Discover more types of non-Mendelian inheritance such as incomplete dominance and co-dominance with the Amoeba Sisters! This video uses vocabulary that was previously defined in the Amoeba Sisters Monohybrid Crosses video. (07:12)

Historically, the closer people lived to each other, the more genetic markers they shared. By using these regional patterns of variation, we can track the migratory paths of your ancestors to tell where you came from. (03:25)

Mutations are fascinating occurrences. Deleting a single base or inserting a new one has the potential to create great change. The Amoeba Sisters will discuss the types of gene and chromosome mutations and also explain how mutations can occur. As a r...eal world example, they'll talk about sickle cell anemia and the remarkable difference between having sickle cell anemia and only being a carrier. Come laugh and learn with the Amoeba Sisters! (07:22)[more]

Heredity is the passing of traits, or features, from parents to offspring through genes. Genes, which are found inside cells, are shared from one generation to the next, passing on all kinds of characteristics like eye color, dimples, freckles, and ...height. Learn more about heredity with this cartoon animation from StudyJams. A short, self-checking quiz is also included with this link.[more]

From something as small and complex as a chromosome to something as seemingly simple as the weather, sex determination systems vary significantly across the animal kingdom. Biologist and teacher Aaron Reedy shows us the amazing differences between sp...ecies when it comes to determination of gender. (05:46)[more]

RNA, the close chemical cousin of DNA, was once thought to be a bit player in the life of a cell, but not anymore. RNA is now at the heart of a scientific and medical revolution. It’s a revolution that started with the cultivation of a purple petunia..., and it has led scientists to what may be the most important advance in biology in decades. Through a process known as RNAi (the "i" is for interference), researchers have a new way to shut off specific genes, yielding insights into the human genome as well as providing potential treatments for a wide range of diseases. A good 15-minute overview.[more]

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